Experiences in infancy are acknowledged to affect the course and outcome of social and mental development in childhood, and they are credited for some of the distinctiveness of culture. More specifically, cross- cultural developmental studies have historically shown that variations in childbearing styles typically have implications for children's later cognitive performance and interpersonal behavior. Home environments are thought to reflect larger cultural values, beliefs, and customs, and many social theorists have contended that the family generally, and the mother-infant relationship specifically, may be vital to development of the individual and basic to the organization of the culture. As a result, investigators have frequently studied infancy and mother-infant interaction in attempts to address questions about the origins and development of cultural identity. Of course, each society has evolved patterns of childbearing adjusted to its own special demands. The primary purpose of this prospective cross-cultural longitudinal project is to identify and trace similarities and differences in the childbearing ecologies of Argentine, Belgian, French, Israeli, Italian, Japanese, and U.S. American Families.